Substractive Output (Product and Waste) > Input (Machining)
Conservative Output (1 out) = Input (1 in)
Additive Output (2 out) < Input (1 in)
Metal Forming Conservative
tidak ada perubahan massa atau volume yang signifikan
menghasilkan barang kompleks dengan mengaplikasikan gaya mekanik dan panas
Form shape + size + accuracy + dimensional tolerance
Properties bulk (instrinsic) dan surface
Form + Properties fungsi tertentu nilai guna
Bulk Metal Forming
Rolling
This is a compressive deformation process in which the thickness of a slab or plate is reduced by two opposing cylindrical tools called rolls. The rolls rotate so as to draw the work into the gap between them and squeeze it.
Forging
In forging, a workpiece is compressed between two opposing dies, so that the die shapes are imparted to the work. Forging is traditionally a hot working process, but many types of forging are performed cold.
Extrusion
This is a compression process in which the work metal is forced to flow through a die opening, thereby taking the shape of the opening as its own cross section.
Drawing
In this forming process, the diameter of a round wire or bar is reduced by pulling it through a die opening.
Sheet Metal Forming
Bending: involves straining of a metal sheet or plate to take an angle along a (usually) straight axis.
Drawing: In sheet metalworking, drawing refers to the forming of a flat metal sheet into a hollow or concave shape, such as a cup, by stretching the metal. A blankholder is used to hold down the blank while the punch pushes into the sheet metal,
Shearing: This process seems somewhat out-of-place in a list of deformation processes, because it involves cutting rather than forming. A shearing operation cuts the work using a punch and die
Bulk Metal Forming
low surface to volume ratio
compressive plastic deformation Sheet metal Forming
high surface to volume ratio
tensile plastic deformation
Tribologi (4): ilmu yang mempelajari tentang friksi, lubrikasi, dan wear
Temperatur Proses Metal Forming Hot Working
Above recrystallization temperature
Allows for large deformation
Less energy required than for cold working
May result in surface oxidation
Cold Working
Below recrystallization temperature
Increases strength, but decreases ductility and corrosion resistance
Direct compressive
Direct compressive force: gaya yang diaplikasikan untuk menyebabkan perubahan geometri. Contoh pada rolling.
Indirect compressive
Ada rolling, yang dia tidak direct, jadi rollnya loose, dan logam ditarik. Tetapi yang ngubah bukan gaya tariknya, tapi karena dia terkena rolls
Menggunakan STARC (Sensors, thermal control, actuator and forming tools, robotic manipulation system, computation). Sehingga dapat melakukan selective heat treatment.